Exemplary embodiments of the invention relate to a method for monitoring and/or controlling and/or regulating the operation of a centrifuge, in particular a separator, during the centrifugal processing of a product, in particular when clarifying a product and/or when separating a product into various liquid phases.
Such methods are known per se from the prior art, such as German patent document DE 4111933 C1, which discloses emptying monitoring on the basis of a measurement of the increase of the current of the drive motor of the drum or a drop of the speed of the drum. Another method is disclosed in German patent document DE 102008062055 A1, which discloses a method for detecting a machine state, in which an analysis of measured values is performed to detect the machine state, wherein the machine controller assigns and evaluates the measured value of a sensor of a machine component depending on the control state.
In relation to this prior art, a further method for monitoring and/or regulating the operation of a centrifuge is to be provided, which enables novel operating modes and analyses in relation to the prior art.
According to exemplary embodiments, force measurements are performed and analyzed using one or more force sensors. In the event of a deviation from a predefined behavior, an output is performed. Optionally or alternatively, the force measurements or the analyses of the force measurements are used during the control and/or regulation of the operation of the centrifuge.
According to the invention, the running operation of the centrifuge during the centrifugal processing of a product is therefore monitored by one or more force measurements using one or more force sensors. A regulation of the operation is then also optionally or alternatively performed. Error recognition is possible and preferably an optimization of the operation of the centrifuge is also possible by way of a regulation depending on predefined limits of the force measurement(s).
For example, detecting axial deflections of the drive spindle using sensors is known from the prior art. In this manner, the operation of a centrifuge can be monitored or at least additionally monitored in a simple manner. The monitoring and control using force sensors, however, provides an alternative possibility for monitoring and controlling in relation to the known methods. Moreover, it may be combined with the known methods. Force sensors or force pickups represent a simple possibility for monitoring and/or controlling and regulating the operation of the centrifuge, which offers different and/or further advantages in relation to the prior art.
Force washers and/or shear force transducers are preferably used to carry out the force measurements.
Inferences about the operating state can be drawn from the measurement data of the force measurements, for example, at spring elements on the base elements and/or on the drum mounting of the centrifuge.
Machine and process and/or method actions for operational optimization are preferably initiated and the effects thereof are monitored by the machine controller (a control and preferably regulating unit) depending on the analysis of the measurement by the machine controller, optionally further state variables of the centrifuge, and optionally the respective method processes.
A centrifuge, in particular a separator having vertical axis of rotation, is preferably set up on four elastic (base) elements, in which a drum is supported on elastic support bearings in the region of the drum mounting. In this way, a movement of the supported system is possible in narrow limits in each case. These movements result from the machine-dynamic state but also the process state of the centrifuge. The static and dynamic forces acting on the base elements and/or the support bearings at the drum mounting can each be determined or measured via the force sensors in the form of force measurements.
The force measurements are preferably each set in relation to one or more reference measurement(s), whereby a judgment of parameters of the present state of the machine, the method process, and/or the respective changes thereof becomes possible. Machine functions, a change of the operating speed, and/or method process functions such as emptying or changing the feed quantity are then initiated depending on static or dynamic limiting values. For this purpose, it is advantageous if a calibration run is carried out once or repeatedly to carry out the reference measurement.